Can corticotomy (with or without bone grafting) expand the limits of safe orthodontic therapy?

Purpose: To assess whether concomitant particulate bone grafting makes a difference in the ability to safely orthodontically reposition teeth outside the bony envelope after corticotomy.

Material and methods: Retrospective analysis of patients who underwent corticotomy as part of their orthodontic therapy for treatment of severe crowding. Patients were divided as: a) Group 1: corticotomy with bone grafting, and, b) Group 2: corticotomy without bone grafting. CT scan examinations were performed before and at the end of the treatment. Measurements of bone and tooth positions were obtained and differences between pre- and post-treatment values were calculated.

Results: The study sample included 20 adult patients between the ages of 25 to 58 years. A total of 144 teeth were orthodontically repositioned outside their native bony envelope after corticotomy. Average follow-up was 9 months. Teeth that were repositioned after corticotomy and bone grafting maintained the alveolar bone volume around them while corticotomy without bone grafting was not successful in maintaining bone thickness around teeth that were moved outside the alveolar housing.

Conclusions: Corticotomy in combination with guided bone regeneration has the potential to increase the scope of conventional orthodontic treatment by allowing for expansive movements beyond the traditional limits.